Many of the Milky Way’s ancient stars derive from other smaller galaxies torn apart by violent galactic collisions, say researchers at Durham University.
Computer simulations show that the stars, found in a halo of debris surrounding the Milky Way, were ripped away by the gravity generated by colliding galaxies five billion years ago.
The computer simulations started from the Big Bang, around 13 billion years ago, and used the universal laws of physics to simulate the evolution of dark matter and the stars.
These simulations are the most realistic yet, says the team, capable of zooming into the very fine detail of the stellar halo structure.